Let's get real here, buckaroos! Even if there is no change in pin position, and no change in wind or temperature and no change in your physical or mental condition, none of the posters here (including me, and the majority of posters on this thread with whom I have actually golfed my ball) will hit their drive, or their second shot, or their recovery shot or their first or second putts to and from the same place in any two consecutive rounds. That is nearly infinite variety with any two plays over the "same" course. Add in the realities of changes in temperature and wind speed and direction and physical and mental status, and the variety increasingly approaches infinity. Adding new pin positions every day is preferable, but it only adds miniscule %s of variety, particularly given the fact that all of us hit the ball with the right line and length only a pitifully small % of the time.
But....the more often we play a shot or a hole or a golf course, the more we learn about the course and about our game. When we play a course (no matter how "great" it may be) only once, all we do is dip our toes into the waters of understanding. When we play a course multiple times (even if it is very much less than "great") we learn (often exponentially) each time we play. We learn less if we play all our courses in parallel, regardles of how good those courses might be. IMHO, of course.
Rich